Process and apparatus for the manufacture of portland cement.



WitnBsses= 14 Inventor v c; P. MQKENNA.

PROCESS-AND APPARATUS FOR THE MANUFACTURE 0P PORTLAND CEMENT. ABPLIQATION FILED JAN. 2, 1907. RENEWED MAR.19,1909. 936,555, Patented 0011.12, 1909.

4 SHEETS-SHEET 1.

W Cizar'ies F Mcfienna c. RMQK NNA. PROCESS AND APPARATUS FOR THE MANUFACTURE OF PORTLAND GEMENT.

APPIFIOATION FILED JAN 2 1907. RENEWED MAR. 19, 1909.-

936,555. Patented dot. 12,1909.

(SHEETB-BHEET 2.

' Inventor Witnesses= Charles F McKenna 0. P. MeKENNA. PROCESS AND APPARATUS FOR THE MANUFACTURE OF PORTLAND CEMENT.

APPLIOATION FILED JAN. 2, 1907. RENEWED MAR. 19, 1909. I

Patented Oct. 12, 1909.

4 SHEETS-SHEET 3.

Ihven m; Uhar i s F Mclfnna;

Witnesses:

Jail-Bra? V 0. IE. McKBNNA. I I PROCESS AND APPARATUS FOR THE MANUFACTURE 0P POBTLAND UEMENT.

APPLIOATIGRIILED JAN. 2, 1907. RENEWED MAR. 19, 1909. 936,555. Patented 001;. 12, 1909.

Invenior Charles F Mck snna 6N NR A Wm 7 Tocll whom it may concern:

- ing 'c'ement raw materials and their pro-1 UNITED-STATES PATENT orrion.

. emanates r. mxnuua, or new YORK, i Y.

PROCESS nun APPARATUS roe THE ANUFACTURE or lOR'lJIJAND CEMENT.

Specification of Letters Patent.

Patented Oct. 12, 1909.

Application filed January 2, 1907, Serial lNo. 350,438. Renewed March 19, 1909. Serial No. 48 E538.

' Be it known that I, CHARLu's F. MCKENNA,

a citizen of the United States of America, and a resident of the borough of Manhattan, in the city ofNew' York, county of New York, and State of New, York, have invented certain new and useful Improvements in .Prooesses'and' Apparatus for the Manufacture of Portland Cement, of which the fol- 1 0 lowing ,is a specification.

This invention relates to'a process of min limina-ry treatment by hydraulic methods,

, and to a process of converting-the raw materials into cement which is especially suited to economic v their hydraulic mining and initial treatract-ice in conjunction with ment.- v

One of the objects of the invention is the economical utilization of caleiferous Ina-- terial in the form of deposits of marl and argillaceous material in the form of de- 'weather and Without the removal of other than the finely divided ccnstituentsof the deposits which are most useful in cement manufacture, thus etfecting a material reduction or elimination of grinding 'preliminary to incorporating" and burning.

Furtherobjects of the invention relate to afi'ording opportunities for examining and correcting composition of the mixed material before its transfer to the kilns.

Further objects of the invention relate to the rapid elimination of .water by screening and-consequent savingin fuel consumption for final evaporation .or drying, and the heating of the material during incorporation and preliminary to its introduction into the kilns whereby further fuel saving is effected, and the utilization of the incorporating mill to arrest and save material which is carried from the kiln with escaping gases.

In the accompanying four sheets of draw,

ings which form a part of this application illustrated paratus embodying my invention and for carrying out 'the embodying my invention, in Which l paratus for the hydraulic mining, elutriation and tlfi-HSPOIli-fltlOIl of the cement I' W malterial's and fuel material, tanks for mixing the elutriat ed materials, and cntrifugals v for screening. Figsf and 4 show respectively elevation and plan views of the parts of the apparatus, comprising bins for screened material, incorporatingmills, and

rotary kilns for producing cement clinker.

Figs. 5 and 6 show respectively elevation and plan 'views of the part-s of the apparatus comprising a clinker cooler, bins for clinker.

. and ball mills and tube mills forfinal grind ing, 7 Fig, 7 shows in vertical section drawn to a larger scale oneof the incorporating The three sheets of drawings containing Figs. 1 to 6 inclusive, read from left to right and in order, show in sequence apparatus for carrying out the successive steps of the complete process from the mining of the 'raw materials to the delivery of the'cementQ- F orthc hydraulic ninin I provide for each of theraw materials individually deposited. as the peat P, marl-M, and cl r C, a hydraulic extractor consisting of a shield, pipe 1 and a water. pipe or nozzlefl wi thinthe shield pipe, which slink \'etically through overlying strata into the material which it is desired to mine and to a sulii cient depth to bring the end below frost in cold weather. The shield pipeis open at the.

through perforations 3 rming a sprayad. jacent to the lowcr cnd of the shield pipe. The two pipes are mechanically held in proper relation to each other by a cap 4 at. the upper end of the shield pipe, the water pipe passing through the cap. i

-.9( lower end and the water fpipe or nozzle opens I In operation'water is drawn from any suitable source, as a well 5, and forced. as by .a pump 6, through pipe connections 7 to the nozzle within the shield pipe. The spray from the nozzle on striking the raw matelOO rial in which the lower part of the shi d pipe is embedded washes out and brings the finer-particles into suspension, leavingf behind the larger and heavier constituents,

up through the annular space between the pipes and through pipe connections 8 and a suction pump 9 into storage tanks, several of which are provided as m. m for the marl, a for theclay, andtgiforthe peat. From these tanks the washing or slurry of calciferous material. is, drawn through'pipe connections 10 and a pump 11, and the washing or slurry of argillaceous material is drawn through ipe connections 12 and a pump 13, both was ings into a tank A and mixed, the composition tested and corrected, and then throu h pipe connections 14 and a pump 15 transfierred. to a tank B. Where natural grades can be availed of for pressure, it. is obvious that the pumpin may be more or less dispensed with. The s urry of fuel material, wh ch may be also made with powdered coal when peat is not available, is drawn through a main 16 and nozzles17 17, and the slurry ofmixed cement materials is drawn through a main 18 and nozzles .19 19 into centrifugals 20 20. A small quantity of fuel material is. first charged, this having the property of' packing against the centrifugal screen and serving as a suitable support and filtering medium for the elutriated cement material as it' is screened,,this cement material being so finely divided that it would pass through loosely in the centrifugal screen if allowed to come in direct contact therewith. Additional fuel material is charged with the cement material asmay be further needed forsupport or for. rovidin porosity in the'screening and use-- 1 in su sequent operations. The screened mixed material is discharged from the centrifugalsinto screw conveyors 21 21, and thence passe'sto a bucket belt conveye'r 22 by which it is elevated to bins 23 23. From either bin the screened material is delivered through a screw conveyer 24 into an incorporating mill'25, the conveyer projecting throu h a hollow trunnion .26 at one end of the cylmder of the mill. This mill .eifects reliminary drying and intimate mixing or mc orporatmg of the cement materials. The

finely;- divided particles after traversing the (:y' iiider pass through screens 27 at the end into chambers 28 formed by radial partitions which elevate the incorporated material and discharge it through a sleeve 29 and screen 30. Any particles which are .too largeto pass through this second screen can pass across it and be discharged into a separate channel, and any particles which fail to pass the first screen can pass out through an interior concentric tube or trunnion 31. Both trunnions of the cylinder are hollow and run flue heads or chambers, one of which 32 communicates with a stack 33, and the other of which also receives one end of a rotary kiln 35. By-pass flues 36 are ro-,

the incorporating mill. The mill is thus em ployedfor preliminary drying and pulver izing so far asmay be necessary as well as for incorporating before discharging the material into the kiln. The mill thus arranged and connected also serves. to catch material which is carried out of the kiln by the es 'caping gases and would otherwise be lost through the stack. A screw-conveyer 38 re-' ceii-es the fine screened material from the incorporating mill and discharges it into the rotary kiln. Opportunity is also afforded for withdrawing samples at this conveyer and testing correctness of composition of the material as it is about to pass into the kiln. 'The kiln is of usual construction and is heated by an ignited- -mixture of powdered fuel and air which is blown *into the kiln from a pipe 39.. The fuel mixed with the cement material also becomes ignited in the 'kiln and contributes to the heat generated by the fuel which is blown in. Upon the, discharge from the kilns the clinker falls on a bucket conveyer40 and is elevated to the top of a cooling tower 41 and discharged. The clinker descends in the towerby gravity over inclined plates 42' in zigzag arrangement which are air "or 'air and water cooled. A parallel zigzag path is provided by a second set of plates 43 for use as a dryer for fuel material which may also be deposited at the top of the tower so as to descend over this set of plates which become heated by the clinker. The cooled clinker is elevated by a belt conveyer 44 to a bin 45 from which it is drawn into a Lindhardball mill 46 such as is shown in United States Patent No. 737,750 dated Sept, 1, 1903. This milleffects the first of the grmdings subsequent to the burning in the kilns. After this grinding the. cement is again elevated by belt conveyers 47 47- to bins 48 48 and drawn therefrom for final grinding in Davidson .tubemills 49 49 containing balls or-pebbles and constructed and operating in a 'manner well known in cement practice; The discharge from these mills is collected by a screw con-- veyer '50.

There are many formsof the detailed apparatus already in the art for effecting many of the steps herein set forth and which may be substituted without departing from the spirit of my invention, and I therefore do not limit myself to the precise apparatus herein illustrated except so far as it is specifically recited in the claims.

As 18 well known the present practice in cement manufacture tends to an exceedingly fine subdivision of the cement materials. To illustrate this'it may be stated that the best modern practice requires the material to be so fine' that seventy-five per cent. thereof will pass through a screen of 40,000

'meshesto the uare inch. *Fine subdivision t ,as essential m the wetprocess hyA individual deposits by draulically minin the materials in the main ner before descri ed, I accomplish this in the process of mining and I secure by grad-- nation the very finestparticles that the mined bed contains.

Vhat I claim as new and desire to secure States, 1s-' byLet-ters Patent of the United 1. The process of working peat, marl, and clay deposits which consists in removing the individual deposits with a hydraulic extractor-,admixing the washings of the severalpassing the same through a screen, and throwing the admixed washings argillaceous materials and ofmarl and clay upon the peat while in the process of screening, whereby the washings of peat serve as a filter for the washings of the other deposits.

'3. The process of mining calciferous and manufacturing Port-land cement therefrom hich consists in separately hydraulically miningand elutri- -atingthe materials whereby particles unsuited for incorporating and burning without: preliminary grinding are eliminated,

jointly screening, drying, incorporating,

burn1ng, and subsequently grinding.

4. The process of'nnmng calciferousand argillaceous materials and manufacturing Port-land cement therefrom which consists in'hydraulic mining and elutrlatlon of the incorporating, burning, r d

. materials, the mixing therewith of fuel material, screening themixed materials, drying.

and subsequently 5. The process'of manufacturing Portland cement-which consists 1n the mlxture of a slurry of finely divided calciferous and argillaceous material with fuel ,material, screening of the mlxed ..mater 1als, drying,

incorporating, burning, and subsequently grinding.

6. The process of manufacturing Portland cement which consists inthe mixture of a slurry of finely divided. calciferous .and

argillaceous material with peat, screening of the mixed materials, drying, incorporating, burning, and subsequently grinding.

7. The process of manufacturing Portland cement which consists in the formation .of a: slurry of calciferous and argillaceous materials, filterin the's'lurry through fuel, burning the 'resufiantresidue, and subsequently grinding. V

8. In a process of manufacturing Portland cement, thepassage of mixedcalciferous and argillaceous material through an incorporating mill and akiln, and theconcurrent passage of the gases from the kiln through-the incorporating mill to a stack.

9. In an apparatus for working marl, and clay deposits,.the combination of a hydraulic extractor for each of said deposits, whereby particles unsuited for incorporating and burning without preliminary grinding are eliminated, means for ad'- mixing the washings from the-- several extractors, a screen for screening the admixed Y incorporating, I

washings, means for drying, burning, and subsequent grinding.

' '10. In an appa'ratus'for manufacturing Portland cement, the combination of an incorporating mill, a kiln and a stack therefor, connectionsfor the passage of gases from the kiln to the stack throughtthe incorporating -mill, and means'for the passing of mixed calciferous and-argillaceous materials into the incorporating-mill and from the incorporating mill into the kiln.

' Signed by me at New York, (borough of Manhattan), N; Y., this thirty-first day of December, 1906.-

CHAS. F. M KENNA. Vitnesses: I SAMUEL WV. BALoH, EDWARD ScHnoEn R.

peat, 

